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Final Rule.
SUMMARY
This regulation establishes tolerances for residues of nicosulfuron in or on sorghum, grain, forage; sorghum, grain, grain; and sorghum, grain, stover. E.I. du Pont de Nemours and Company requested these tolerances under the Federal Food, Drug, and Cosmetic Act (FFDCA).
TABLE OF CONTENTS
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DATES:
ADDRESSES:
FOR FURTHER INFORMATION CONTACT:
SUPPLEMENTARY INFORMATION:
I. General Information
A. Does this action apply to me?
B. How can I get electronic access to other related information?
C. How can I file an objection or hearing request?
II. Summary of Petitioned-For Tolerance
III. Aggregate Risk Assessment and Determination of Safety
A. Toxicological Profile
B. Toxicological Points of Departure/Levels of Concern
C. Exposure Assessment
D. Safety Factor for Infants and Children
E. Aggregate Risks and Determination of Safety
IV. Other Considerations
A. Analytical Enforcement Methodology
B. International Residue Limits
C. Revisions to Petitioned-For Tolerances
V. Conclusion
VI. Statutory and Executive Order Reviews
VII. Congressional Review Act
List of Subjects in 40 CFR Part 180
PART 180—[AMENDED]
TABLES
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Table 1—Summary of Toxicological Doses and Endpoints for Nicosulfuron for Use in Human Health Risk Assessment
DATES:
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This regulation is effective November 4, 2015. Objections and requests for hearings must be received on or before January 4, 2016, and must be filed in accordance with the instructions provided in 40 CFR part 178 (see also Unit I.C. of the SUPPLEMENTARY INFORMATION).
ADDRESSES:
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The docket for this action, identified by docket identification (ID) number EPA-HQ-OPP-2013-0034, is available at http://www.regulations.gov or at the Office of Pesticide Programs Regulatory Public Docket (OPP Docket) in the Environmental Protection Agency Docket Center (EPA/DC), West William Jefferson Clinton Bldg., Rm. 3334, 1301 Constitution Ave. NW., Washington, DC 20460-0001. The Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding legal holidays. The telephone number for the Public Reading Room is (202) 566-1744, and the telephone number for the OPP Docket is (703) 305-5805. Please review the visitor instructions and additional information about the docket available at http://www.epa.gov/dockets.
FOR FURTHER INFORMATION CONTACT:
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Susan Lewis, Registration Division (7505P), Office of Pesticide Programs, Environmental Protection Agency, 1200 Pennsylvania Ave. NW., Washington, DC 20460-0001; main telephone number: (703) 305-7090; email address: RDFRNotices@epa.gov.
SUPPLEMENTARY INFORMATION:
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I. General Information
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A. Does this action apply to me?
You may be potentially affected by this action if you are an agricultural producer, food manufacturer, or pesticide manufacturer. The following list of North American Industrial Classification System (NAICS) codes is not intended to be exhaustive, but rather provides a guide to help readers determine whether this document applies to them. Potentially affected entities may include:
Crop production (NAICS code 111).
Animal production (NAICS code 112).
Food manufacturing (NAICS code 311).
Pesticide manufacturing (NAICS code 32532).
B. How can I get electronic access to other related information?
You may access a frequently updated electronic version of EPA's tolerance regulations at 40 CFR part 180 through the Government Printing Office's e-CFR site at http://www.ecfr.gov/cgi-bin/text-idx?&c=ecfr&tpl=/ecfrbrowse/Title40/40tab_02.tpl.
C. How can I file an objection or hearing request?
Under FFDCA section 408(g), 21 U.S.C. 346a, any person may file an objection to any aspect of this regulation and may also request a hearing on those objections. You must file your objection or request a hearing on this regulation in accordance with the instructions provided in 40 CFR part 178. To ensure proper receipt by EPA, you must identify docket ID number EPA-HQ-OPP-2013-0034 in the subject line on the first page of your submission. All objections and requests for a hearing must be in writing, and must be received by the Hearing Clerk on or before January 4, 2016. Addresses for mail and hand delivery of objections and hearing requests are provided in 40 CFR 178.25(b).
In addition to filing an objection or hearing request with the Hearing Clerk as described in 40 CFR part 178, please submit a copy of the filing (excluding any Confidential Business Information (CBI)) for inclusion in the public docket. Information not marked confidential pursuant to 40 CFR part 2 may be disclosed publicly by EPA without priornotice. Submit the non-CBI copy of your objection or hearing request, identified by docket ID number EPA-HQ-OPP-2013-0034, by one of the following methods:
Federal eRulemaking Portal: http://www.regulations.gov. Follow the online instructions for submitting comments. Do not submit electronically any information you consider to be CBI or other information whose disclosure is restricted by statute.
Mail: OPP Docket, Environmental Protection Agency Docket Center (EPA/DC), (28221T), 1200 Pennsylvania Ave. NW., Washington, DC 20460-0001.
Hand Delivery: To make special arrangements for hand delivery or delivery of boxed information, please follow the instructions at http://www.epa.gov/dockets/contacts.html.
Additional instructions on commenting or visiting the docket, along with more information about dockets generally, is available at http://www.epa.gov/dockets.
II. Summary of Petitioned-For Tolerance
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In the Federal Register of July 19, 2013 (78 FR 43117) (FRL-9392-9), EPA issued a document pursuant to FFDCA section 408(d)(3), 21 U.S.C. 346a(d)(3), announcing the filing of a pesticide petition (PP 2F8132) by E.I. du Pont de Nemours and Company, 1007 Market Street, Wilmington, DE 19898. The petition requested that 40 CFR 180.454 be amended by establishing tolerances for residues of the herbicide nicosulfuron, 3-pyridinecarboxamide, 2-((((4,6-dimethoxypyrimidin-2-yl)aminocarbonyl)aminosulfonyl))-N,N-dimethyl, in or on sorghum, forage at 0.4 parts per million (ppm); sorghum, grain at 0.8 ppm; and sorghum, stover at 0.05 ppm. That document referenced a summary of the petition prepared by E.I. du Pont de Nemours and Company, the registrant, which is available in the docket, http://www.regulations.gov. There were no comments received in response to the notice of filing.
Based upon review of the data supporting the petition, EPA has revised the proposed commodity definitions, revised the proposed tolerance level for “sorghum, grain, forage”, and corrected the typographical error in the chemical name of nicosulfuron in the tolerance expression. Also, EPA has removed the expired emergency exemption tolerances for Bermuda grass, forage and Bermuda grass, hay. The reasons for these changes are explained in Unit IV.C.
III. Aggregate Risk Assessment and Determination of Safety
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Section 408(b)(2)(A)(i) of FFDCA allows EPA to establish a tolerance (the legal limit for a pesticide chemical residue in or on a food) only if EPA determines that the tolerance is “safe.” Section 408(b)(2)(A)(ii) of FFDCA defines “safe” to mean that “there is a reasonable certainty that no harm will result from aggregate exposure to the pesticide chemical residue, including all anticipated dietary exposures and all other exposures for which there is reliable information.” This includes exposure through drinking water and in residential settings, but does not include occupational exposure. Section 408(b)(2)(C) of FFDCA requires EPA to give special consideration to exposure of infants and children to the pesticide chemical residue in establishing a tolerance and to “ensure that there is a reasonable certainty that no harm will result to infants and children from aggregate exposure to the pesticide chemical residue. . . .”
Consistent with FFDCA section 408(b)(2)(D), and the factors specified in FFDCA section 408(b)(2)(D), EPA has reviewed the available scientific data and other relevant information in support of this action. EPA has sufficient data to assess the hazards of and to make a determination on aggregate exposure for nicosulfuron including exposure resulting from the tolerances established by this action. EPA's assessment of exposures and risks associated with nicosulfuron follows.
A. Toxicological Profile
EPA has evaluated the available toxicity data and considered its validity, completeness, and reliability as well as the relationship of the results of the studies to human risk. EPA has also considered available information concerning the variability of the sensitivities of major identifiable subgroups of consumers, including infants and children.
Nicosulfuron has low acute toxicity by oral, dermal, and inhalation routes of exposure. It is moderately irritating to the eye, non-irritating to the skin, and is not a skin sensitizer. In repeated dose studies by the oral route, nicosulfuron is minimally toxic, and rodents are particularly insensitive to its effects. Chronic dietary administrations to rats and mice did not produce any adverse effects at the highest dose tested (HDT). Chronic dietary administration to dogs produced mild effects (increased relative liver and kidney weights of males) at the HDT.
Nicosulfuron showed no developmental effects in rats, and no adverse effects were observed in the rat reproductive study. In the rabbit developmental study, abortions occurred at the doses that caused other maternal toxicity effects. There are no indications of neurotoxic or immunotoxic effects elicited by nicosulfuron in animal studies; this includes recently submitted acute and subchronic neurotoxicity studies and an immunotoxicity study. There is no evidence of mutagenicity.
Nicosulfuron is classified as “Not Likely to be Carcinogenic to Humans” based on lack of evidence of carcinogenicity in rats and mice studies and lack of mutagenic effects in the in vitro and in vivo genotoxicity studies.
Specific information on the studies received and the nature of the adverse effects caused by nicosulfuron as well as the no-observed-adverse-effect-level (NOAEL) and the lowest-observed-adverse-effect-level (LOAEL) from the toxicity studies can be found at http://www.regulations.gov in document “Nicosulfuron: Human Health Risk Assessment for Proposed Use on ALS Inhibitor Tolerant Sorghum,” pp. 24-27 in docket ID number EPA-HQ-OPP-2013-0034.
B. Toxicological Points of Departure/Levels of Concern
Once a pesticide's toxicological profile is determined, EPA identifies toxicological points of departure (POD) and levels of concern to use in evaluating the risk posed by human exposure to the pesticide. For hazards that have a threshold below which there is no appreciable risk, the toxicological POD is used as the basis for derivation of reference values for risk assessment. PODs are developed based on a careful analysis of the doses in each toxicological study to determine the dose at which no adverse effects are observed (the NOAEL) and the lowest dose at which adverse effects of concern are identified (the LOAEL). Uncertainty/safety factors are used in conjunction with the POD to calculate a safe exposure level—generally referred to as a population-adjusted dose (PAD) or a reference dose (RfD)—and a safe margin of exposure (MOE). For non-threshold risks, the Agency assumes that any amount of exposure will lead to some degree of risk. Thus, the Agency estimates risk in terms of the probability of an occurrence of the adverse effect expected in a lifetime. For more information on the general principles EPA uses in risk characterization and a complete description of the risk assessment process, see http://www.epa.gov/pesticides/factsheets/riskassess.htm.
A summary of the toxicological endpoints for nicosulfuron used for human risk assessment is shown in Table 1 of this unit.
Table 1—Summary of Toxicological Doses and Endpoints for Nicosulfuron for Use in Human Health Risk Assessment Back to Top
Exposure/scenarioPoint of departure and uncertainty/safety factorsRfD, PAD, LOC for risk assessmentStudy and toxicological effects
FQPA SF = Food Quality Protection Act Safety Factor. LOAEL = lowest-observed-adverse-effect-level. mg/kg/day = milligram/kilogram/day. NOAEL = no-observed-adverse-effect-level. cPAD = chronic population adjusted dose. RfD = reference dose. UF = uncertainty factor. UF A= extrapolation from animal to human (interspecies). UF H= potential variation in sensitivity among members of the human population (intraspecies).
Chronic dietary (All populations)NOAEL= 125 mg/kg/day UF A= 10x UF H= 10x FQPA SF = 1xChronic RfD = 1.25 mg/kg/day cPAD = 1.25 mg/kg/dayChronic oral toxicity—Dog. LOAEL = 500 mg/kg/day based on increased relative liver and kidney weights in males. Supported by rabbit developmental toxicity study (NOAEL = 100 mg/kg/day, LOAEL = 500 mg/kg/day).
C. Exposure Assessment
1. Dietary exposure from food and feed uses. In evaluating dietary exposure to nicosulfuron, EPA considered exposure under the petitioned-for tolerances as well as all existing nicosulfuron tolerances in 40 CFR 180.454. EPA assessed dietary exposures from nicosulfuron in food as follows:
i. Acute exposure. Quantitative acute dietary exposure and risk assessments are performed for a food-use pesticide, if a toxicological study has indicated the possibility of an effect of concern occurring as a result of a 1-day or single exposure. No such effects were identified in the toxicological studies for nicosulfuron; therefore, a quantitative acute dietary exposure assessment is unnecessary.
ii. Chronic exposure. In conducting the chronic dietary exposure assessment EPA used the food consumption data from the USDA's 2003-2008 National Health and Nutrition Examination Survey, What We Eat in America (NHANES/WWEIA). As to residue levels in food, EPA assumed that nicosulfuron residues were present at tolerance levels in all commodities for which tolerances have been established or proposed, and that 100% of those crops were treated with nicosulfuron.
iii. Cancer. Based on the data summarized in Unit III.A., EPA has concluded that nicosulfuron does not pose a cancer risk to humans. Therefore, a dietary exposure assessment for the purpose of assessing cancer risk is unnecessary.
iv. Anticipated residue and percent crop treated (PCT) information. EPA did not use anticipated residue and/or PCT information in the dietary assessment for nicosulfuron. Tolerance level residues and/or 100 PCT were assumed for all food commodities.
2. Dietary exposure from drinking water. The Agency used screening-level water exposure models in the dietary exposure analysis and risk assessment for nicosulfuron in drinking water. These simulation models take into account data on the physical, chemical, and fate/transport characteristics of nicosulfuron. Further information regarding EPA drinking water models used in pesticide exposure assessment can be found at http://www.epa.gov/oppefed1/models/water/index.htm.
Based on the Pesticide Root Zone Model/Exposure Analysis Modeling System (PRZM/EXAMS) and Pesticide Root Zone Model Ground Water (PRZM-GW), the estimated drinking water concentrations (EDWCs) of nicosulfuron for chronic exposures for non-cancer assessments are estimated to be 2.8 ppb for surface water and 19.2 ppb for ground water. Based on the Screening Concentration in Ground Water (SCI-GROW) model, the EDWC of nicosulfuron for chronic exposures for non-cancer assessments are estimated to be 1.42 ppb.
Modeled estimates of drinking water concentrations were directly entered into the dietary exposure model. For chronic dietary risk assessment, the water concentration value of 19.2 ppb was used to assess the contribution to drinking water.
3. From non-dietary exposure. The term “residential exposure” is used in this document to refer to non-occupational, non-dietary exposure (e.g., for lawn and garden pest control, indoor pest control, termiticides, and flea and tick control on pets). Nicosulfuron is not registered for any specific use patterns that would result in residential exposure.
4. Cumulative effects from substances with a common mechanism of toxicity. Section 408(b)(2)(D)(v) of FFDCA requires that, when considering whether to establish, modify, or revoke a tolerance, the Agency consider “available information” concerning the cumulative effects of a particular pesticide's residues and “other substances that have a common mechanism of toxicity.”
EPA has not found nicosulfuron to share a common mechanism of toxicity with any other substances, and nicosulfuron does not appear to produce a toxic metabolite produced by other substances. For the purposes of this tolerance action, therefore, EPA has assumed that nicosulfuron does not have a common mechanism of toxicity with other substances. For information regarding EPA's efforts to determine which chemicals have a common mechanism of toxicity and to evaluate the cumulative effects of such chemicals, see EPA's Web site at http://www.epa.gov/pesticides/cumulative.
D. Safety Factor for Infants and Children
1. In general. Section 408(b)(2)(C) of FFDCA provides that EPA shall apply an additional tenfold (10X) margin of safety for infants and children in the case of threshold effects to account for prenatal and postnatal toxicity and the completeness of the database on toxicity and exposure unless EPA determines based on reliable data that a different margin of safety will be safe for infants and children. This additional margin of safety is commonly referred to as the FQPA Safety Factor (SF). In applying this provision, EPA either retains the default value of 10X, or uses a different additional safety factor when reliable data available to EPA support the choice of a different factor.
2. Prenatal and postnatal sensitivity. No evidence of increased sensitivity or susceptibility in the developing or young animal was observed in the current database. No treatment-relatedeffects were seen for maternal or developmental toxicity up to and including the HDT in the rat prenatal developmental study, and no adverse effects were noted in the rat reproductive study. Although increases in abortions and post-implantation losses were observed in the rabbit developmental study, those effects occurred at the same doses as other maternal toxicity, indicating that they were a secondary effect of maternal toxicity, rather than a developmental or reproductive effect.
3. Conclusion. EPA has determined that reliable data show the safety of infants and children would be adequately protected if the FQPA SF were reduced to 1x. That decision is based on the following findings:
i. The toxicity database for nicosulfuron is complete.
ii. There is no indication that nicosulfuron is a neurotoxic chemical and there is no need for a developmental neurotoxicity study or additional UFs to account for neurotoxicity.
iii. There is no evidence that nicosulfuron results in increased susceptibility in in utero rats or rabbits in the prenatal developmental studies or in young rats in the 2-generation reproduction study.
iv. There are no residual uncertainties identified in the exposure databases. The dietary food exposure assessments were performed based on 100 PCT and tolerance-level residues. EPA made conservative (protective) assumptions in the ground and surface water modeling used to assess exposure to nicosulfuron in drinking water. These assessments will not underestimate the exposure and risks posed by nicosulfuron.
E. Aggregate Risks and Determination of Safety
EPA determines whether acute and chronic dietary pesticide exposures are safe by comparing aggregate exposure estimates to the acute PAD (aPAD) and chronic PAD (cPAD). For linear cancer risks, EPA calculates the lifetime probability of acquiring cancer given the estimated aggregate exposure. Short-, intermediate-, and chronic-term risks are evaluated by comparing the estimated aggregate food, water, and residential exposure to the appropriate PODs to ensure that an adequate MOE exists.
1. Acute risk. An acute aggregate risk assessment takes into account acute exposure estimates from dietary consumption of food and drinking water. No adverse effect resulting from a single oral exposure was identified and no acute dietary endpoint was selected. Therefore, nicosulfuron is not expected to pose an acute risk.
2. Chronic risk. Using the exposure assumptions described in this unit for chronic exposure, EPA has concluded that chronic exposure to nicosulfuron from food and water will utilize <1% of the cPAD for the general U.S. population and all population subgroups including infants and children. There are no residential uses for nicosulfuron.
3. Short- and intermediate-term risks. Short- and intermediate-term aggregate exposure takes into account short- and intermediate-term residential exposure plus chronic exposure to food and water (considered to be a background exposure level). Because there are no residential uses, no short- or intermediate-term aggregate risk assessments were conducted.
4. Aggregate cancer risk for U.S. population. Based on the lack of evidence of carcinogenicity in two adequate rodent carcinogenicity studies, nicosulfuron is not expected to pose a cancer risk to humans.
5. Determination of safety. Based on these risk assessments, EPA concludes that there is a reasonable certainty that no harm will result to the general population, or to infants and children from aggregate exposure to nicosulfuron residues.
IV. Other Considerations
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A. Analytical Enforcement Methodology
Adequate enforcement methodology (Method DuPont-32277, a high performance liquid chromatography with tandem mass spectroscopy (HPLC/MS/MS)) is available to enforce the tolerance expression. The method may be requested from: Chief, Analytical Chemistry Branch, Environmental Science Center, 701 Mapes Rd., Ft. Meade, MD 20755-5350; telephone number: (410) 305-2905; email address: residuemethods@epa.gov.
B. International Residue Limits
In making its tolerance decisions, EPA seeks to harmonize U.S. tolerances with international standards whenever possible, consistent with U.S. food safety standards and agricultural practices. EPA considers the international maximum residue limits (MRLs) established by the Codex Alimentarius Commission (Codex), as required by FFDCA section 408(b)(4). The Codex Alimentarius is a joint United Nations Food and Agriculture Organization/World Health Organization food standards program, and it is recognized as an international food safety standards-setting organization in trade agreements to which the United States is a party. EPA may establish a tolerance that is different from a Codex MRL; however, FFDCA section 408(b)(4) requires that EPA explain the reasons for departing from the Codex level.
The Codex has not established MRLs for nicosulfuron.
C. Revisions to Petitioned-For Tolerances
The Agency is revising the proposed commodity definitions of “sorghum, forage” to “sorghum, grain, forage”; “sorghum, grain” to “sorghum, grain, grain”; and “sorghum, stover” to “sorghum, grain, stover” for consistency with EPA's Food and Feed Commodity Vocabulary. The proposed tolerance level of 0.4 ppm for “sorghum, forage” is revised to 0.3 ppm for “sorghum, grain, forage” based on analysis of the residue field trial data using the Organization for the Economic Cooperation and Development's tolerance calculation procedure. The tolerance expression is revised to correct the typographical error in the chemical name for nicosulfuron.
V. Conclusion
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Therefore, tolerances are established for residues of nicosulfuron, 2-[[[[(4,6-dimethoxy-2-pyrimidinyl)amino]carbonyl]amino]sulfonyl]-N,N- dimethyl-3-pyridinecarboxamide, including its metabolites and degradates, in or on sorghum, grain, forage at 0.3 ppm; sorghum, grain, grain at 0.8 ppm; and sorghum, grain, stover at 0.05 ppm.
In addition, as a housekeeping measure, the Agency is removing the expired emergency exemption tolerances on “Bermuda grass, forage” and “Bermuda grass, hay”. The tolerances expired on December 31, 2011.
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